CI/CD Integration

CI/CD runs your tests and checks automatically on every code change.

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What Is CI/CD?

Term	Meaning
CI (Continuous Integration)	Automatically build and test code on every push
CD (Continuous Delivery)	Automatically prepare code for release
CD (Continuous Deployment)	Automatically deploy to production

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Basic CI Pipeline

Every CI pipeline should include these steps:

1. Install dependencies
2. Run linters (ruff, mypy)
3. Run tests (pytest)
4. Check coverage
5. Generate reports

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GitHub Actions Example

# .github/workflows/ci.yml
name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Install uv
        uses: astral-sh/setup-uv@v4

      - name: Set up Python
        run: uv python install 3.12

      - name: Install dependencies
        run: uv sync

      - name: Run linter
        run: uv run ruff check .

      - name: Run type checker
        run: uv run mypy src/

      - name: Run tests
        run: uv run pytest --cov=src --cov-report=xml

      - name: Check coverage
        run: uv run pytest --cov=src --cov-fail-under=100

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GitLab CI Example

# .gitlab-ci.yml
stages:
  - lint
  - test

variables:
  UV_SYSTEM_PYTHON: "true"

lint:
  stage: lint
  image: python:3.12
  script:
    - pip install uv
    - uv sync
    - uv run ruff check .
    - uv run mypy src/

test:
  stage: test
  image: python:3.12
  script:
    - pip install uv
    - uv sync
    - uv run pytest --cov=src --junitxml=report.xml
  artifacts:
    reports:
      junit: report.xml

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Test Reporting

JUnit XML (Standard Format)

uv run pytest --junitxml=report.xml

Most CI systems can read JUnit XML and show test results in the UI.

Allure Reports

uv add --dev allure-pytest
uv run pytest --alluredir=allure-results

Allure creates rich HTML reports with:

• Test history
• Screenshots
• Step-by-step logs
• Trends

HTML Coverage Report

uv run pytest --cov=src --cov-report=html

This creates an htmlcov/ folder with a visual coverage report.

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Pipeline Best Practices

Fail Fast

Put the fastest checks first:

1. Ruff (seconds)      → catches syntax and style issues
2. mypy (seconds)      → catches type errors
3. Unit tests (seconds) → catches logic bugs
4. Integration tests (minutes) → catches integration issues
5. E2E tests (minutes)  → catches user flow issues

Cache Dependencies

# GitHub Actions
- uses: actions/cache@v4
  with:
    path: ~/.cache/uv
    key: uv-${{ hashFiles('uv.lock') }}

Run on Every PR

• Run all checks on every pull request
• Block merge if any check fails
• Keep pipeline under 10 minutes

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Quality Gates

Set rules that must pass before code can be merged:

Gate	Rule
Linting	Zero ruff errors
Type checking	Zero mypy errors
Tests	All tests pass
Coverage	>= 100% line coverage
No secrets	No API keys in code

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Best Practices

• Run all checks on every pull request
• Fail fast — put quick checks first
• Cache dependencies to speed up pipelines
• Keep pipelines under 10 minutes
• Generate test reports (JUnit XML, Allure)
• Set quality gates and enforce them
• Use branch protection — require passing CI before merge
• Run the same checks locally and in CI